Furnace troubleshooting

Top Lennox® Furnace Error Codes (and What They Mean)

While your Lennox® HVAC equipment can’t speak to you, it does have a way to tell you about a furnace error.

Its motherboard has a set of LED lights that can show a fault code. Depending on the fault, your furnace may show continuous or flashing lights.

While there are certain elementary furnace adjustments you can complete without an expert, the majority of services are best handled by HVAC technicians. When your furnace won’t turn on or deliver heated air, call Crome Mechanical at 616-200-7264 for expert furnace repair in Rockford.

Our experts will quickly identify and repair the malfunction, even if you don’t have a Lennox furnace. We can fix whichever types or makes—and get the comfort restored to your home quickly.


What Does the Flickering Light on My Heating System Mean?

Your furnace depends on lights to flash code when it requires repairs. It also uses this system to let you know it’s heating correctly.

Normal function involves:

  • Concurrent slow flash—heater working like it should.
  • Simultaneous fast flash—furnace is starting to call for heat.

If you see a single light going on and off slowly and the other going on and off rapidly, your heating system may be experiencing a low flame signal. This can occur even when your furnace is running properly. It indicates the flame sensing rod could have build-up or in the incorrect spot on the burner. Reach out to us at 616-200-7264 for help.

Here are a few other of the most typical faults for Lennox HVAC systems.

Heating System Will Not Kick On

Here are some of the light arrangements you may notice when your heater will not or keep running. The bulk of these issues need to be repaired by a specialist, such as one from Crome Mechanical.

  1. Both LED lights are extinguished. This signifies your heating system might not have power. Check the breaker box to confirm the furnace fuse isn’t tripped. You should reset the fuse if it is in the “off” area. If it immediately flips following a reset, don’t try to reset it again and contact us at 616-200-7264.
  2. A single light is unchanging and the other is blinking slowly. This means the flame rollout switch is possibly not working right. The part is an essential safety device that aids in avoiding fires and carbon monoxide. You shouldn’t seek to take care of this problem on your own.
  3. A single light is flickering rapidly and the other is blinking slowly. This typically indicates power polarity has been reversed. Your heating system may have a wiring issue that requires professional aid from Crome Mechanical.
  4. Both lights are flashing slowly. This signifies your furnace’s blower motor probably isn’t operating. This part distributes warm air from the HVAC system into your house. We can help in figuring out what’s wrong with this component.
  5. A single light is flickering slowly and the other is flickering fast. This signifies your heater might have low voltage or a short circuit. Get in touch with our experts at 616-200-7264 for help.
  6. One light is flashing on, on and off while the other flickers on, off, on. This signifies there might be an issue with your heater’s motherboard or wiring. Crome Mechanical can find the problem and fix it.
  7. Both lights display alternate slow blinks. This means your HVAC equipment likely has a flame problem. There could be trouble with its gas supply, gas valve or ignitor control. Call us at 616-200-7264 for help.
  8. One light flashes slowly while the other remains solid. This usually signifies your heater’s limit switch is malfunctioning. The switch keeps your furnace from getting too hot. Contact the experts at Crome Mechanical for help.

Heater Blower Operates But No Heat

Here’s what might be wrong when you hear your heater’s blower fan working, but you aren’t getting any warmth.

  • The pair of lights are giving alternate fast flickers. This means your furnace ignitor could be broken. This piece lights fuel in your heater to produce heat and should be serviced by a professional from Crome Mechanical.

Depend on Us for Professional Furnace Repair

When you have to have your heating system in working order fast, depend on the specialists at Crome Mechanical. Our techs will fix the problem promptly and have your house feeling cozy again in a short time. Contact us at 616-200-7264 or contact us online to request an appointment now.

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